Composition and support material comprising poly(9,9&#39;-spiro-bisfluorenes)

ABSTRACT

Soluble poly(bis-9,9&#39;-fluorenes) comprise identical or different structural repeating units of the formula I, ##STR1## where the two R 1  s are, independently of one another, H, C 1-C   18  alkyl, C 6  -C 14  aryl, C 7  -C 15  aralkyl, C 1  -C 18  alkoxy, R 2  --(O--C n  H 2n ) m  --O--, C 1  -C 18  alkylthio, C 1  -C 18  dialkylamino, --C(O)OH, --C(O)O-C 1  -C 18  alkyl, --C(O)--N(C 1  -C 18  alkyl) 2 , --SO 3  H, --SO 3  -C 1  -C 18  alkyl, --SO 2  --N(C 1  -C 18  alkyl) 2 , C 1  -C 17  -alkyl-C(O)--O-- or C 1  -C 17  alkyl-C(O)--, R 2  is H or C 1  -C 12  alkyl, n is from 2 to 6 and m is from 1 to 12. 
     The polymers can be used either alone or in admixture with at least one additional fluorophore whose absorption band overlaps the emission band (fluorescent emission) of the polymer of the formula I as active radiative layer for light-emitting diodes, VDUs and display elements.

The present invention relates to unsubstituted and substitutedpoly(9,9'-spirobisfluorenes); a process for their preparation; acomposition comprising a support material and a layer of anunsubstituted or substituted poly(9,9'-spirobisfluorene), which may, ifdesired, further comprise a luminophore; a composition comprising anunsubstituted or substituted poly(9,9'-spirobisfluorene) which comprisesa luminophore; and the use of the compositions or thepoly(9,9'-spirobisfluorenes) as fluorophores, for example inlight-emitting diodes or electrodes in display applications, and also2,2'-dihalo-7,7'-disubstituted 9,9'-bisfluorenes.

In recent times, materials which emit fluorescent radiation haveattracted greatly increased interest for display elements orphotodiodes. In Adv. Mater. 1994, 6, No. 3, pages 190 to 198, J. M. Tourdescribes polyphenylenes which are known to emit blue fluorescent light.The good mechanical and thermal properties of the polyphenylenes areknown. The insolubility in organic solvents and the associatedunsatisfactory processibility and also the instability of dopedpolyphenylenes greatly impairs commercial utilization. There is a greatneed for blue-fluorescing and processible materials based on aromatichydrocarbons, which materials have excellent thermal and mechanicalproperties (for example thermal stabilities above 200° C.); the polymersshould be able to be prepared easily and, in particular, the targetedpreparation of defined polymers should be possible. Furthermore, it isdesirable for the polymers to be suitable as matrix for theincorporation of small amounts of different fluorophores in order toobtain fluorescent emissions over the entire visible spectrum.

It has now surprisingly been found that 9,9'-bisfluorenes can bepolymerized to give blue-fluorescing polymers which are soluble in manysolvents and are therefore also readily processible, for example bymeans of customary coating processes. The polymers have excellentthermal and mechanical stabilities and are excellent matrix systems forthe incorporation of molecular fluorophores which can be used influorescent displays and in electroluminescent displays.

The invention provides, firstly, soluble poly(bis-9,9'-fluorenes)comprising identical or different structural repeating units of theformula I, ##STR2## where the two R₁ s are, independently of oneanother, H, C₁ -C₁₈ alkyl, C₆ -C₁₄ aryl, C₇ -C₁₅ aralkyl, C₁ -C₁₈alkoxy, R₂ --(O--C_(n) H_(2n))_(m) --O--, C₁ -C₁₈ alkylthio, C₁ -C₁₈dialkylamino, --C(O)OH, --C(O)O-C₁ -C₁₈ alkyl, --C(O)--N(C₁ -C₁₈alkyl)₂, --SO₃ H, --SO₃ -C_(1-C) ₁₈ alkyl, --SO₂ --N(C₁ -C₁₈ alkyl)₂, C₁-C₁₇ alkly-C(O)--O-- or C₁ -C₁₇ alkyl-C(O)--, R₂ is H or C₁ -C₁₂ alkyl,n is from 2 to 6 and m is from 1 to 12.

The alkyl groups in alkyl, alkoxy, alkylthio, diaminoalkyl, carboxylicester or sulfonic ester, carboxamide or sulfonamide, alkyl-CO₂ -- andalkyl-C(O)-- radicals R₁ can be linear or branched and preferablycontain from 1 to 12, particularly preferably from 1 to 8, C atoms. Someexamples of alkyl are methyl, ethyl, n- and i-propyl, n-, i- andt-butyl, and the isomers of pentyl, hexyl, heptyl, octyl, nonyl, decyl,undecyl, dodecyl, tetradecyl, hexadecyl and octadecyl.

Aryl radicals R₁ preferably contain from 6 to 10 C atoms. Some examplesare naphthyl, biphenylyl and, particularly preferably, phenyl.

Aralkyl radicals R₁ preferably contain from 7 to 12 C atoms and thealkylene group in the aralkyl radical preferably contains 1 or 2 Catoms. A preferred example is benzyl and also phenylethyl.

Halogen atoms R₁ are preferably F, Cl or Br.

Alkyl radicals R₂ preferably contain from 1 to 8 and particularlypreferably from 1 to 4 C atoms. They can be linear or branched. Someexamples are methyl, ethyl, n-propyl and n-butyl.

In the radical R₂ --(O--C_(n) H_(2n))_(m) --O--, n is preferably from 2to 4, particularly preferably 2 or 3.

In the radical R₂ ---(O--C_(n) H_(2n))_(m) --O--, m is preferably from 1to 8, particularly preferably from 1 to 6.

In a preferred embodiment of the invention, the two R₁ s in the polymersof the formula I are identical radicals as defined above.

In a preferred embodiment of the invention, each R₁ in the polymers ofthe formula I is H, C₁ -C₁₂ alkyl-C(O)-- or C₁ -C₁₂ alkoxy.

The polymers of the invention can be crosslinked, which dependsessentially on the method of preparation. The degree of crosslinking canbe so high that a virtually only crosslinked low molecular weightpolymer, which is, however, still soluble, is obtained. Such polymerscomprise structural units of the formula Ia, Ib or both structuralunits, ##STR3## where R₁ is as defined above.

Structural units of the formula Ia are formed from monosubstituted9,9'-bisfluorenes and structural units of the formula Ib are formed fromunsubstituted 9,9'-bisfluorene.

The degree of polymerization (number of structural repeating units) canbe from 2 to 100, more preferably from 3 to 50, even more preferablyfrom 3 to 40 and particularly preferably from 5 to 30. The term polymersthus also encompasses oligomers. In general, the polymers of theinvention comprise polymer chains having different degrees ofpolymerization (chain lengths).

The polymers of the invention can be prepared by methods known per seand by methods analogous to those described in the literature.

The invention further provides a process for preparingpoly(bis-9,9'-fluorenes) comprising identical or different structuralrepeating units of the formula I, ##STR4## and, if desired, identical ordifferent structural units of the formulae ##STR5## where R₁ is asdefined above, which process comprises cationically-oxidativelypolymerizing a) at least one halogen-free 9,9'-bisfluorene of theformula II, ##STR6## where R₁ is as defined above, in the presence of aninert solvent.

Examples of suitable solvents are N,N-disubstituted carboxamides andN-substituted lactams (dimethylformamide, N-methylpyrrolidone), esters(butyl acetate), ethers (dibutyl ether), sulfoxides (dimethylsulfoxide), sulfones (tetramethylene sulfone), aliphatic and aromatichydrocarbons (toluene, xylene), halogenated or nitrated aliphatic andaromatic hydrocarbons (carbon tetrachloride, tetrachloroethane) andcarbon disulfide.

The cationic-oxidative polymerization has been described for benzene byP. Kovacic et al. in Tetrahedron Letters No. 11, pages 467 to 469 (1962)and can also be employed analogously for the polymerization of9,9'-spirobisfluorenes.

The polymerization is carried out, for example, using oxidizing Lewisacids such as FeCl₃ or using Lewis acids, mainly metal halides such asAlCl₃, AlBr₃, BF₃ or BCl₃, in combination with an oxidizing agent suchas a metal compound having a relatively high oxidation state. Use isfrequently made of CuCl₂. Oxidizing agents such as KMnO₄, Fe⁺³ salts andbenzoquinone derivatives such as tetrachlorobenzoquinone can also beused. It is also possible to employ electrochemical oxidation in asuitable organic solvent for effecting the polymerization.

The molar ratio of spirobisfluorene to catalyst or Lewis acid can befrom 1:0.2 to 1:2, preferably from 1:0.4 to 1:1.5 and particularlypreferably from 1:0.5 to 1:1.2. The molar ratio of Lewis acid tooxidizing agent can be, for example, from 1:0.2 to 1:1, preferably from1:0.3 to 1:0.8 and particularly preferably from 1:0.4 to 1:0.6.

The reaction temperature is preferably from 20° C. to 200° C., morepreferably from 20° C. to 150° C., particularly preferably from 20° C.to 100° C. and most particularly preferably from 30° C. to 80° C.

The reaction can be carried out, for example, by adding the catalyst tothe dissolved spirobisfluorene, if desired heating the mixture andallowing it to react for some time (for example up to 24 hours) whilestirring. The polymer formed can then be precipitated and filtered offor the solvent can be removed. To remove the Lewis acids/oxidizingagents, the residues can be washed with water, dried and then treatedwith solvents such as methylene chloride or tetrahydrofuran to isolatethe desired soluble polymers.

In this polymerization method, crosslinked polymers are frequentlyformed and insoluble polymers can easily be removed. The degree ofcrosslinking can be influenced by the reaction conditions, for examplethe monomer concentration in the reaction mixture, the amount ofcatalyst and the ratio of catalyst to oxidizing agent, and by thereaction temperature.

Another way of preparing the polymers of the invention is from2,2'-halogenated 9,9'-spirobisfluorenes using a method similar to thatdescribed by T. Yamamoto et al. in Bulletin of the Chemical Society ofJapan, Vol. 51 (7), pages 2091 to 2097 (1978) and Macromolecules 25,pages 1214 to 1223 (1992). This method is preferred since polymershaving a defined structure can be prepared in a targeted manner.

The invention also provides a process for preparingpoly(bis-9,9'-fluorenes) comprising identical or different structuralrepeating units of the formula I, ##STR7## where R₁ is as defined above,which process comprises reacting a 2,2'-dihalo-9,9'-spirobisfluorene ofthe formula III, ##STR8## where R₁ is as defined above and X is halogen,in the presence of an inert solvent, an alkali metal or alkaline earthmetal and a transition metal complex or metal salt of a transitionmetal.

X is preferably F, Cl or Br, more preferably Cl or Br and particularlypreferably Br.

Suitable solvents are mainly the solvents used for Grignard reactions,for example aromatic hydrocarbons such as benzene, toluene, xylene,nitrobenzene and ethers such as diethyl ether, dipropyl ether, dibutylether, tetrahydrofuran, dioxane, ethylene glycol diethyl ether, ethyleneglycol dimethyl ether and diethylene glycol dimethyl ether.

As alkali metals and alkaline earth metals, use is frequently made ofLi, Na, K, Zn, Cd, Mg and Ca; particular preference is given to Li andMg.

A great many suitable transition metal complexes are known. Thetransition metal complexes can be those of metal ions or unchargedmetals. Some examples of metals are Fe, Co, Ni, Mo, Cr, W and noblemetals such as Pt, Pd, Ru, Ir and Os. In the case of metal ioncomplexes, the anions can be derived from inorganic or organic acids,for example acetic acid, benzoic acid, toluenesulfonic acid, sulfuricacid and hydrohalic acids. Preference is given to metal halidecomplexes. Examples of uncharged ligands are open-chain and cyclic1,3-dienes (cyclohexadiene, cyclooctadiene), nitriles (acetonitrile andbenzonitrile), ethers, alcohols, tertiary phosphines (triphenylphosphineand tricyclohexylphosphine), ditertiary diphosphines, tertiary aminesand ditertiary diamines such as bipyridine. Some examples of metalcomplexes are Ni(cyclooctadiene)₂ in admixture with P(C₆ H₅)₃, Ni[P(C₆H₅)₃ ]₄, NiCl₂ (bipyridine)₂, NiBr₂ [P(C₆ H₅)₃ ]₂, Pd(Cl)₂(bipyridine)₂, NiCl₂, CoCl₂, FeCl₂ and FeCl₃.

The amount of alkali metals or alkaline earth metals is preferablyequimolar to the amount of dihalo-9,9'-spirobisfluorene, but a slightexcess can also be used. The amount of transition metal complexes ortransition metal salts is preferably likewise equimolar, but a slightexcess or deficiency can be used.

The reaction can take place even under mild conditions at roomtemperature. A higher temperature of, for example, up to 150° C.,preferably up to 100° C., accelerates the reaction.

The polymerization can be carried out by combining the reactioncomponents with the solvent, then heating the mixture and allowing it toreact to completion. To avoid excessively long induction times, a smallamount of elemental iodine, for example, can be added. The reaction canalso be carried out by first preparing the corresponding organometalliccompound (Grignard compound) from the dihalo-9,9'-spirobisfluorene andan alkali metal or alkaline earth metal or a corresponding metal alkyland only then adding a transition metal complex.

The polymers can be isolated in a customary manner, for example byfiltering off insoluble constituents of the reaction mixture, washing toremove salts, precipitation or removing the solvent. The polymers can bepurified by reprecipitation and, if appropriate, washing.

Some of the compounds of the formula II are known or they can beprepared by methods known per se.

2,2'-Dibromo-9,9'-spirobisfluorene can be prepared by direct brominationof 9,9'-spirobisfluorene in the presence of Lewis acids such as FeBr₃(V. Prelog et al., Helvetica Chimica Acta 52(5), page 4253 (1969). Theresulting product mixtures of compounds having different degrees ofbromination and positional isomers can be purified by recrystallizationand chromatographic methods. 2,2'-Dinitro-9,9'-spirobisfluorene can beprepared by the method of J. Weissenburger, JACS, page 4253 (1950) andisolated in pure form from the product mixture by recrystallization andchromatographic methods. The dinitro compound can, for example, bereduced using iron in ethanol to give the diamine, then diazotized andreacted with CuBr to form 2,2'-dibromo-9,9'-spirobisfluorene.

2,2'-Diamino-9,9'-spirobisfluorene can be converted into thecorresponding N,N,N',N'-tetraalkyl compounds by means of alkylatingagents. The reaction of the dibromo compounds with organometallichydrocarbon compounds (Grignard compounds) leads to the dialkyl ordiaryl derivatives. Substitution with alcohols, thiols orpolyoxaalkylenediol monoethers gives the alkoxy-, alkylthio- andpolyoxaalkylenoxy-substituted derivatives.

Diazotized 2,2'-dinitro-9,9'-spirobisfluorene can be converted by meansof concentrated sulfuric acid into 2,2'-dihydroxy-9,9'-spirobisfluorenewhich can be esterified in a manner known per se.2,2'-Dimethyl-9,9'-spirobisfluorene can be oxidized in a customarymanner to give the carboxylic acid and then esterified or amidated.9,9'-Spirobisfluorene-2,2'-sulfonic acid is obtainable in a known mannerby oxidation of 9,9'-spirobisfluorene-2,2'-dithiol, with the dithiolbeing obtainable by nucleophilic substitution of2,2'-dibromo-9,9'-spirobisfluorene.

2,2'-Diacyl-9,9'-spirobisfluorenes can be obtained in a simple mannerand in high yields by Friedel-Crafts acylation using carboxylic acidhalides in the presence of Lewis acids such as AlCl₃.

It has surprisingly been found that the dihalo compounds of the formulaIII are obtained in high yields and regioselectivity from the compoundsof the formula I in which R₁ is not a hydrogen atom if the reaction iscarried out using elemental halogen, for example Cl₂, Br₂ or I₂,preferably Br₂, in the presence of an excess of a Lewis acid.

The invention further provides compounds of the formula IV, ##STR9##where X is halogen and

R₃ is C₁ -C₁₈ alkyl, C₆ -C₁₄ aryl, C₇ -C₁₅ aralkyl, C₁ -C₁₈ alkoxy, R₂--(O--C_(n) H_(2n))_(m) --O--, C₁ -C₁₈ alkylthio, C₁ -C₁₈ dialkylamino,--C(O)OH, --C(O)O-C₁ -C₁₈ alkyl, --C(O)--N(C₁ -C₁₈ alkyl)₂, --SO₃ H,--SO₃ -C₁ -C₁₈ alkyl, --SO₂ --N(C₁ -C₁₈ alkyl)₂, C₁ -C₁₇ alkyl-C(O)--O--or C₁ -C₁₇ alkyl-C(O)--, R₂ is H or C₁ -C₁₂ alkyl, n is from 2 to 6 andm is from 1 to 12.

X is preferably Cl, Br or I, more preferably Cl or Br, and particularlypreferably Br.

For R₃, the preferences and preferred embodiments given for R₁ informula I apply.

The invention also provides a process for preparing the compounds of theformula IV, which comprises reacting a compound of the formula V,##STR10## where R₃ is as defined above, in an inert solvent withelemental halogen in the presence of an excess of a Lewis acid.

The reaction temperature can be from room temperature to 200° C.,preferably from 20 to 100° C. and particularly preferably from 20 to 50°C. The reaction is particularly preferably carried out at roomtemperature, which may require cooling at the beginning of the reaction.

The halogen is preferably used in equimolar amounts.

Suitable solvents are polar aprotic solvents which can be used alone orin mixtures. Some examples are open-chain or cyclic ethers, carbondisulfide and halogenated aliphatic or cycloaliphatic hydrocarbons.

Examples of suitable Lewis acids are BF₃, BCl₃, AlBr₃, AlCl₃, ZnCl₂,ZnBr₂, FeCl₂, FeCl₃, FeBr₂, FeBr₃, TiCl₄, TiBr₄, SnCl₂, SnBr₂, SnCl₄ andSnBr₄. Preference is given to using AlCl₃ or AlBr₃.

Excess can mean that the Lewis acids otherwise used in catalytic amountsin halogenation reactions of aromatics are present in an amount of atleast 1 mol, preferably at least 2 mol, more preferably at least 4 moland particularly preferably at least 10 mol, based on 1 mol of thecompound of the formula V.

The isolation of the desired compounds and their purification can becarried out in a customary manner; purification itself is often notnecessary since by-products are formed only in small amounts. Thecompounds of the invention are, depending on substitution, crystallineor amorphous solids which are soluble in polar aprotic solvents and aretherefore readily processible. Even the monomers have a bluishfluorescence and are well suited to preparing defined and generallyuncrosslinked polymers.

Despite the stiff structural units, the polymers of the invention arestill soluble in customary organic solvents and can therefore be usedand readily processed in solution as coating materials. They have veryhigh thermal stabilities, glass transition temperatures and excellentmechanical properties. Furthermore, the poly(bis-9,9'-fluorenes) of theinvention have absorption bands in the wavelength region below about 400nm, and fluorescence emission maxima at wavelengths of from about 420 to460 nm. They are thus blue-fluorescing materials which have beenprovided for the first time as processible polymers.

The invention further provides a composition comprising (a) a solventand (b) a poly(bis-9,9'-fluorene) having identical or differentstructural repeating units of the formula I.

The amount of dissolved poly(bis-9,9'-fluorene) depends essentially onthe solvent, the degree of polymerization and crosslinking and thesubstitution. The solutions according to the invention can contain from0.01 to 80% by weight, preferably from 0.01 to 60% by weight, morepreferably from 0.01 to 50% by weight, particularly preferably from 0.1to 30% by weight and very particularly preferably from 0.1 to 20% byweight, of poly(bis-9,9'-fluorene, based on the total amount of thecomposition.

The composition of the present invention can comprise further additives,for example processing aids, agents for improving the mechanical andthermal properties, agents for improving the appearance or agents forimproving the adhesion properties. Some examples are fluidizers, oradhesion promoters, dyes, pigments, heat stabilizers and lightstabilizers, antistatics, antioxidants, lubricants, mold release agents,fillers, reinforcing fillers and viscosity-increasing substances.

In a particularly preferred embodiment, the composition of the invention(solution) further comprises at least one fluorescent dye (fluorophore).Preference is given to those fluorescent dyes whose absorption bandoverlaps the emission band (fluorescent emission) of the polymer of theinvention. The amount of additional fluorescent dye can be, for example,from 0.000001 to 10% by weight, preferably from 0.00001 to 5% by weight,more preferably from 0.0001 to 3% by weight, particularly preferablyfrom 0.001 to 3% by weight and very particularly preferably from 0.001to 2% by weight, based on the amount of polymer. Many such dyes areknown. Some examples are rhodamines, fluoresceins, cumarins,distyrylbiphenyls, stilbenes, phthalocyanines, naphthalocyanines, metalcomplexes of transition metals and lanthanide metals. It is alsopossible to use fluorescent latent pigments (solubilized pigments havingsolubilizing substituents such as detachable protective groups) selectedfrom the group consisting of diketopyrrolopyrroles or quinacridones,fluorescent perylene derivatives or fluorescent perinones. It islikewise possible to use commerical products such as Lumogen L Yellow®,Brilliant Yellow®, Yellow Orange® or Red Orange® (BASF) and also2,2'-dihydroxybipyridyls and related compounds. Molecularly dispersed(dissolved) fluorescent pigments can also be used. Such compositions areobtainable by dissolving pigments solubilized by means of protectivegroups in the polymer of the invention and subsequently splitting offthe protective group, for example by heating.

The composition (solution) of the invention can be processed in moldswith removal of the solvent, if desired with application of vacuum, toproduce free-standing moldings and films. The polymers obtained can bedoped with, for example, iodine or salts such as alkali metalhexafluorometalates and used as electric conductors, for example aselectrodes. The solutions are of particular importance for coatingsupport materials.

The invention furthermore provides a support material which is coated onat least one side with a polymer according to the invention.

In a preferred embodiment, the polymer layer comprises at least onefurther fluorophore dispersed homogeneously in the polymer layer; theemission band of the polymer preferably overlaps the absorption band ofthe fluorophore. By means of the content of additional fluorophores, allcolors of the visible spectrum can be generated by selection ofdifferent emissions in the visible region, with the polymer itselfhaving a blue fluorescence. This blue basic fluorescence can bereinforced by blue-emitting fluorophores or modified. The preferredamounts and some selected fluorophores have been indicated above.

A great number of support materials are known. The support material canbe an inorganic or organic support material. The support material can beopaque, translucent or transparent. Preference is given to transparentsupport materials. Examples of suitable support materials are plastics,glass, cermics, minerals, rocks, metal oxides and metal mixed oxides,metal nitrides, metal carbides, semiconductors, transparent electricconductors (for example ITO-glass, glass supports coated with SnO₂ /In₂O₃), metals and metal alloys.

The luminescence of the polymers of the invention and their mixtureswith fluorophores can also be stimulated by electric conductors(electrofluorescence). A particularly advantageous embodiment of theinvention is therefore an electroluminescent composition comprising anelectric conductor as support material which is coated on at least oneside with a polymer according to the invention either alone or inadmixture with at least one additional fluorophore. The coating ispreferably connected to a counterelectrode which is particularlypreferably transparent.

The electric conductors can, depending on the application, be opaque,translucent or transparent and be semiconductors or metallic conductors.Transparent conductors are preferably glasses coated with semiconductingmetal oxides or mixtures of metal oxides.

The thickness of the polymer layer can be, for example, from 0.1 to 1000μm, preferably from 1 to 500 μm and particularly preferably from 10 to200 μm.

The coated support material can be produced in a manner known per se bydipping, painting or casting processes, particularly spin coating, withthe thickness of the layer being able to be determined by means of thecontent of polymer and, if used, fluorophore in the solution and also byselection of the process conditions.

The polymers and coated support materials of the invention can be usedwherever markings by means of fluorophores are to be detected ordecorative effects are to be achieved. The coated electric conductorscan be used particularly advantageously as light-emitting diodes for theentire visible spectrum. Transparent, coated electrodes are alsosuitable for VDUs or display elements of electronic image reproductionsystems.

The invention further provides for the use of the polymers, if desiredadditionally doped with at least one further fluorophore, of theinvention as active radiative layer for light-emitting diodes, VDUs anddisplay elements.

The following examples illustrate the invention.

A) Preparation of 9,9'-spirobisfluorenes

Example A1: Preparation of 2,2'-dibromo-9,9'-spirobisfluorene

A solution of 0.7 g of 2,2'-diamino-9,9'-spirobisfluorene in 90 ml ofhalf-concentrated aqueous HBr is stirred at from 0 to ° C. with 0.338 gof NaNO₂ in 20 ml of water for one hour and the excess sodium nitrite isthen destroyed using urea. Subsequently, at 0° C., a solution of 0.701 gof CuBr in 50 ml of half-concentrated aqueous HBr is added and themixture is stirred for two days at room temperature. The product whichhas precipitated is filtered off, washed with 2N aqueous NaOH and thenwith water. Reprecipitation from methanol gives the title compound in ayield of 47%.

¹ H-NMR (400 Mhz, CDCl₃, TMS): 7.81 (d, J=7.6 Hz, 2H, 3-H); 7.70 (d,J=8.2 Hz, 2H, 4-H); 7.50 (dd, J=8.2 and 1.8 Hz, 2H, 3-H); 7.38 (td,J=7.6 Hz and 0.9, 2H, 6-H); 7.14 (td, J=7,6 and 0.9 Hz, 2H, 7-H); 6.84(sd, J=1.8 Hz, 2H, 1-H); 6.71 (d, J=7.6, 2H, 8-H).

Example A2: Preparation of 2,2'-dihydroxy-9,9'-spirobisfluorene

A solution of 0.7 g of 2,2'-diamino-9,9'-spirobisfluorene in 70 ml ofhalf-concentrated sulfuric acid is admixed at from 0 to 5° C. with asolution of 0.337 g of NaNO₂ in 20 ml of water and the mixture isstirred for one hour. The reaction solution is added to 40 ml ofconcentrated sulfuric acid and stirred under reflux for one hour. Theprecipitate is filtered off and washed with water, giving the titlecompound in a yield of 74%.

Example A3: Preparation of 2,2'-dihexanoyl-9,9'-spirobisfluorene

A solution of 31.6 mmol of 9,9'-spirobisfluorene is added to asuspension of 79.1 mmol of finely divided AlCl₃ and 69.9 mmol ofhexanoyl chloride in 100 ml of CS₂. The mixture is stirred for one hourat room temperature and then poured into 40 ml of ice-cold water. Themixture is acidified with hydrochloric acid and the two phases areseparated. The aqueous phase is extracted once with methylene chloride.The combined organic phases are then washed with water and dried overanhydrous potassium carbonate. The solvent is then evaporated and thetitle compound having a melting point of 142° C. is obtained inquantitative yield. Elemental analysis [found (theoretical)]: C 86.51%(86.68); H 7.04% (7.08); O 6.25% (6.24).

Example A4: Preparation of2,2'-dibromo-7,7'-dihexanoyl-9,9'-spirobisfluorene

A solution of 28.5 mmol of 2,2'-dihexanoyl-9,9'-spirobisfluorene in 50ml of CS₂ is slowly added to a stirred suspension of 0.171 mmol offinely divided AlCl₃ in 100 ml of CS₂ and the mixture is then refluxedfor one hour. The reaction solution is cooled and 57 mmol of bromine in50 ml of CS₂ are then added. The mixture is stirred overnight at roomtemperature with exclusion of light. The reaction mixture is then pouredonto a mixture of 300 ml of ice and 30 ml of hydrochloric acid and thephases are separated. The aqueous phase is washed twice with 200 ml ofCS₂. The combined organic phases are washed with 300 ml of five percentaqueous sodium bicarbonate solution and then dried over Na₂ SO₄.Evaporation of the solvent gives the title compound in a yield of 95%.Elemental analysis [found (theoretical)]: C 64.98% (66.28); H 4.87%(5.11); Br 25.33% (23.83) O 4.48% (4.77).

B) Preparation of Polymers

Example B1-B4: Direct polymerization of 9,9'-spirobisfluorene (SBF)

1 Mol of 9,9'-spirobisfluorene is polymerized at 30° C. in CS₂ usingAlCl₃ /CuCl. Further information may be found in Table 1. PSBF ispoly(9,9'-spirobisfluorene). The polymers are amorphous and light brown,blue-fluorescing solids. When analyzed by GPC using polystyrene asstandard, the polymer of Example B2 gives an M_(n) of 2684 and an M_(w)of 16 516. A degree of polymerization of up to 31 is found by MALDI-MSanalysis. The polymer B1 softens at 349° C. and decomposes at 434° C.The other data determined by differential thermal analysis are shown inTable 2.

                                      TABLE 1                                     __________________________________________________________________________                    Proportion of cross-                                                                   Proportion of polymer                                                                   Total                                           AlCl.sub.3                                                                       CuCl                                                                             Reaction                                                                           linked polymer                                                                         soluble in CH.sub.2 Cl.sub.2                                                            yield                                      Example                                                                            (mol)                                                                            (mol)                                                                            time (h)                                                                           (% of PSBF)                                                                            (% of PSBF)                                                                             (%)                                        __________________________________________________________________________    B1   0.5                                                                              0.25                                                                              2   23       77        13                                         B2   1.0                                                                              0.5                                                                              12   18       82        19                                         B3   1.2                                                                              0.6                                                                               2   59       59        11                                         B4   2  1.35                                                                             24   98        2        43                                         __________________________________________________________________________

                  TABLE 2                                                         ______________________________________                                        Polymer       Decomposition                                                                             5% weight                                           from Example  temperature (° C.)                                                                 loss at                                             ______________________________________                                        B2            426         550                                                 B3            414         640 (10%)                                           B4            421         657                                                 ______________________________________                                    

Example B5: Polymerization of 2,2'-dibromo-9,9'-spirobisfluorene

1 g (2.11 mmol) of 2,2'-dibromo-9,9'-spirobifluorene together with 394mg (2.53 mmol) of bipyridyl, 228 mg (2.11 mmol) of cyclooctadiene (COD)and 422 mg (2.53 mmol) of Ni(COD)₂ are dispersed in 20 ml ofdimethylformamide (DMF). This dispersion is heated to 60° C. under inertgas (argon) and stirred at this temperature for 5 days. The polymerformed is precipitated in methanol acidified with HCl (100-150 ml),filtered, washed with methanol, dilute hydrochloric acid and water andsubsequently dried at 50° C. in vacuo. This gives 0.605 g (91% oftheory) of a blue-fluorescing polymer which is soluble intetrahydrofuran, DMF and CH₂ Cl₂. MALDI-MS analysis indicates a degreeof polymerization of about 12. GPC analysis using polystyrene asstandard indicates an M_(n) of 2264 and an M_(w) of 9213.

Example B6: Polymerization of2,2'-dibromo-7,7'-dihexanoyl-9,9-spirobisfluorene

1 g (1.47 mmol) of 2,2'-dibromo-7,7'-dihexanoyl-9,9'-spirobifluorenetogether with 274 mg (1.76 mmol) of bipyridyl, 158 mg (1.47 mmol) of CODand 293 mg (1.76 mmol) of Ni(COD)₂ are dispersed in 15 ml of DMF. Thedispersion is heated to 70° C. and stirred at this temperature for 4days under inert gas (argon). The further procedure is as described inExample B5. This gives 690 mg (90.5% of theory) of a blue-fluorescingpolymer which is soluble in tetrahydrofuran, dimethylformamide and CH₂Cl₂. GPC analysis using polystyrene as standard indicates an M_(n) of3681 and an M_(w) of 6306. The decomposition temperature of the polymeris 308° C. and the weight loss at 600° C. is 35%.

C) Use Examples

Example C1:

The polymer from Example B2 or Example B5 is dissolved in CH₂ Cl₂ and a100 nm thick film on a quartz plate is produced by means of spin coatingand the absorption and emission spectra are measured. In both cases, theabsorption maximum is at λ_(max) =370 nm and the emission maximum is atλ_(max) =420 nm. To measure the emission spectrum, the specimen isirradiated at the absorption maximum (370 nm) and the radiation emittedis measured as a function of wavelength using an apparatus suitable forthis purpose (fluorescence spectrometer).

Example C2:

A film is produced as described in Example C1 from the polymer asdescribed in Example B6. The absorption spectrum is broadened comparedto Example C1 and has two absorption maxima at λ_(max) =340 and 355 nm.The emission maximum is at λ_(max) =430 nm.

Example C3:

A film is produced as described in Example C1 from the polymer asdescribed in Example B6, with 0.5% by weight of a fluorophore beingadditionally dissolved in the solution. The results are shown in Table3.

                                      TABLE 3                                     __________________________________________________________________________                               Photoluminescence (.sub.max)                       Fluorophore        Absorption (.sub.max)                                                                 (emission maximum)                                 __________________________________________________________________________     ##STR11##         437     503                                                 ##STR12##         480     565                                                 ##STR13##         479     655                                                __________________________________________________________________________

What is claimed is:
 1. A composition comprisinga) a solvent; b) asoluble poly(bis-9,9'-fluorene) consisting essentially of identical ordifferent structural repeating units of the formula I, ##STR14## wherethe two R₁ s are, independently of one another, H, C₁ -C₁₈ alkyl, C₆-C₁₄ aryl, C₇ -C₁₅ aralkyl, C₁ -C₁₈ alkoxy, R₂ --(O--C_(n) H_(2n))_(m)--O--, C₁ -C₁₈ alkylthio, C₁ -C₁₈ dialkylamino, --C(O)OH, --C(O)O-C₁-C₁₈ alkyl, --C(O)--N(C₁ -C₁₈ alkyl)₂, --SO₃ H, --SO₃ -C₁ -C₁₈ alkyl,--SO₂ --N(C₁ -C₁₈ alkyl)₂, C₁ -C₁₇ -alkyl-C(O)--O-- or C₁ -C₁₇alkyl-C(O)--, R₂ is H or C₁ -C₁₂ alkyl, n is from 2 to 6 and m is from 1to 12; and c) at least one fluorescent dye (fluorophore) whoseabsorption band overlaps the emission band (fluorescent emission) of thepolymer of formula I.
 2. A composition according to claim 1, wherein thealkyl groups in alkyl, alkoxy, alkylthio, diaminoalkyl, carboxylic esteror sulfonic ester, carboxamide or sulfonamide, alkyl-CO₂ -- andalkyl-C(O)-- radicals R₁ in the poly(bis-9,9'-fluorene) of the formula Iof component b) are linear or branched and contain from 1 to 12 carbonatoms.
 3. A composition according to claim 1, wherein the aryl radicalsR₁ in the poly(bis-9,9'-fluorene) of the formula I of component b)contain from 6 to 10 carbon atoms.
 4. A composition according to claim1, wherein the aralkyl radicals R₁ in the poly(bis-9,9'-fluorene) of theformula I of component b) contain from 7 to 12 carbon atoms and thealkylene group in the aralkyl radical contains 1 or 2 carbon atoms.
 5. Acomposition according to claim 1, wherein the two R₁ s in thepoly(bis-9,9'-fluorene) of the formula I of component b) are identicalradicals.
 6. A composition according to claim 1, wherein each R₁ in thepoly(bis-9,9'-fluorene) of the formula I of component b) is H, C₁ -C₁₂alkyl-C(O)-- or C₁ -C₁₂ alkoxy.
 7. A composition according to claim 1,wherein the degree of polymerization is from 2 to
 100. 8. A compositionaccording to claim 1, wherein the degree of polymerization is from 3 to50.
 9. A composition according to claim 1, wherein the degree ofpolymerization is from 3 to
 40. 10. A composition according to claim 1,wherein the degree of polymerization is from 5 to
 30. 11. A compositionaccording to claim 1, wherein the amount of dissolvedpoly(bis-9,9'-fluorene) of the formula I of component b) is from 0.01 to80% by weight, based on the total weight of the composition.
 12. Acomposition according to claim 1, wherein the amount of component c) isfrom 0.00001 to 10% by weight, based on the amount of the polymer ofcomponent b).
 13. A composition according to claim 1, wherein thefluorescent dye of component c) is a rhodamine, fluorescein, cumarin,distyrylbiphenyl, stilbene, phthalocyanine, naphthalocyanine, or a metalcomplex of a transition metal or lanthanide metal.
 14. A supportmaterial which is coated on at least one side with apoly(bis-9,9'-fluorene) consisting essentially of identical or differentstructural repeating units of the formula I, ##STR15## where the two R₁s are, independently of one another, H, C₁ -C₁₈ alkyl, C₆ -C₁₄ aryl, C₇-C₁₅ aralkyl, C₁ -C₁₈ alkoxy, R₂ --(O--C_(n) H_(2n))_(m) --O--, C₁ -C₁₈alkylthio, C₁ -C₁₈ dialkylamino, --C(O)OH, --C(O)O-C₁ -C₁₈ alkyl,--C(O)--N(C₁ -C₁₈ alkyl)₂, --SO₃ H, --SO₃ -C₁ -C₁₈ alkyl, --SO₂ --N(C₁-C₁₈ alkyl)₂, C₁ -C₁₇ -alkyl-C(O)--O-- or C₁ -C₁₇ alkyl-C(O)--, R₂ is Hor C₁ -C₁₂ alkyl, n is from 2 to 6 and m is from 1 to 12,havinghomogeneously dispersed therein at least one fluorescent dye(fluorophore) which has an absorption band overlaps the emission band(fluorescent emission) of the polymer of formula I.
 15. A supportmaterial according to claim 14 which is an inorganic or organic supportmaterial.
 16. A support material according to claim 14 which is opaque,translucent or transparent.
 17. A support material according to claim 14which is selected from the group consisting of plastics, glass,ceramics, minerals, rocks, metal oxides and metal mixed oxides, metalnitrides, metal carbides, semiconductors, transparent electricconductors, metals and metal alloys.
 18. A support material according toclaim 14, wherein the thickness of the poly(bis-9,9'-fluorene) layer isfrom 0.1 to 1000 μm.